The present invention relates to a fading on and fading off electronic switch suitable for natural light-simulated control of illumination and fading on and off reduced voltage on/off control of electrical heaters. The fading process of the switch go on automatically after on/off guiding operation.
In the prior art, electrical devices like illumination apparatus, motor, and electrical heater are all turned on and off suddenly at the whole voltage, and their transition processes are determined by the physical inertia parameters of the devices themselves and can not be controlled or adjusted. In many cases, it can not meet the demand of the people, or even cause damage to users. In some large or special equipment that needs reduction start or reduction shut down, an equipment which adjusts a series-connected adjustable resistance apparatus is often used to control the on/off transition process. In some more critical applications, analog computing apparatus comprising the combination of open loop or close loop proportional integral, differential or inertia stages or even digital program-controlled apparatus or special industry-control computers are used to automatically control various transition processes including start and shut down. However, these apparatus or computer are very expensive, and go beyond the category of fading on/off switch. As to illumination control, specially designed fading on/off illumination control equipments including voltage regulator and transistor continuous light regulator are used in some high-grade theatres. The operating process of these equipments all belong to man-machine close-loop realtime operation and must be carried out in coordination with the on/off operations of switches. Among the continuous light regulated apparatus for home use, a single point touch switch is developed recently. This switch detects the touch operation by using body induction signal, and controls the trigger of a thyristor by phase regulation performed by built-in IC circuits. Trigger angle will be held when people stop touching the apparatus, and instantaneous touch will cause the on/off states to exchange. Appearently, this also belongs to man-machine close loop real time operation. Up to now, commercially available light-adjustable lamps are also products of this category. To sum up, no convenient and cheap switch which fades on/off automatically when it is turned on/off is provided in the prior art.